The original freshwater system on a
were pump faucets connected to supply bottles under the counters in the galley and head. The water is manually pumped using the pump handle on the faucet. I have an original faucet and supply pigtail in my junk box in the garage, but I do not have any water jugs. If you need a photo, let me know and I'll try and get one for you.
That being said, depending on how much you think you will use it, I'm not sure I'd put any significant money or effort into getting the original faucets working. I would simply keep a jug of water handy for when its needed. If you feel you need a true freshwater supply system you can get a 12V freshwater pump and a small PVC tank that you can use to build one. In my boat I installed the pump and tank under the forward dinette seat. Total cost was about $200. The pump and faucet come in a kit, like this...
https://www.defender.com/product.jsp?pa ... id=3021085
I never use the faucet in the head, even though it is hooked up.
With respect to cooling the cabin, without any shore power, your only options are 12v fans and open hatches. The fans will likely be cheaper at a RV supply house than at a marine store. Eventually you might want to install a Nicro type solar powered vent to help exhaust the interior and prevent condensation, but that isn't going to offer much cooling for you.
